Background: Concern has been raised that the workload of community pharmacists (CPs) is linked to the occurrence of dispensing errors (DEs). One aspect of workload that has not yet been measured in this setting, but has been linked to errors in other industries, is mental workload (MWL). Aims: (1) Measure the relationship between MWL and DEs during a routine pharmacy task, the final accuracy check, which research suggests is critical to DE prevention. (2) Quantify the role that expertise plays in this relationship. (3) Explore CPs and pharmacy students’ experiences of MWL and DEs. Methods: A mixed methods approach was taken and three studies were conducted. In study one, CPs (n=104) and students (n=93) checked dispensed items for DEs. Participants took part in one of four conditions (distraction, no distraction, dual-task or single-task) and their DE detection and MWL was measured. Study two was a diary study of CPs’ (n=40) MWL during a day in their “real-life” practice. Study three presented an interpretative phenomenological analysis of CPs’ (n=14) and students’ (n=15) experiences of MWL and DEs. Main findings: Study one found that high MWL was related to reduced DE detection, but only for students, confirming the important role of expertise. Distractions did not affect DE detection but was linked to increased MWL. Study 2 highlighted specific times of the day when CPs’ MWL was exceptionally high. Study 3 found several factors which increased MWL, including the lack of control CP’s had over their workload, difficulties communicating with prescribers and targets. Conclusions: MWL has been found to be a useful tool for measuring the impact of workload on pharmacy safety. The findings are linked to current work design and human factors theory and suggestions are made for how CPs’ work could be redesigned to reduce their MWL and improve safety.

yes / Background: Experience-Based Co-Design (EBCD) is a participatory design method which was originally developed and is still primarily used as a healthcare quality improvement tool. Traditionally, EBCD has been sited within single services or settings and has yielded improvements grounded in the experiences of those delivering and receiving care. Method: In this article we present how EBCD can be adapted to develop complex interventions, underpinned by theory, to be tested more widely within the healthcare system as part of a multi-phase, multi-site research study. We begin with an outline of co-design and the stages of EBCD. We then provide an overview of how EBCD can be assimilated into an intervention development and evaluation study, giving examples of the adaptations and research tools and methods that can be deployed. We also suggest how to appraise the resulting intervention so it is realistic and tractable in multiple sites. We describe how EBCD can be combined with different behaviour change theories and methods for intervention development and finally, we make suggestions about the skills needed for successful intervention development using EBCD. Conclusion: EBCD has been recognised as being a collaborative approach to improving healthcare services that puts patients and healthcare staff at the heart of initiatives and potential changes. We have demonstrated how EBCD can be integrated into a research project and how existing research approaches can be assimilated into EBCD stages. We have also suggested where behaviour change theories can be used to better understand intervention change mechanisms.